Ensuring safety of young athletes and employees who perform hard physical work within the scope of their professional duties, with a special focus on prevention of a sudden cardiac death at sports fields or during hard physical work is one of the most important tasks, which demands joint effort of cardiologists and sport physicians or occupational physicians, who qualify patients for a job or a sport discipline. Apart from hypertrophic and arhythmogenic right ventricular cardiomyopathy, coronary anomalies and aortic dissection belong to the most frequent causes of dramatic complications during competitive exercise or work with an increased energy expenditure. Although a detailed medical history and a physical examination combined with 12-lead ECG assessment may significantly improve the safety in competitive sports, adding echocardiography examination gives a detailed and noninvasive insight into the heart morphology and function. Therefore, in our opinion, it should constitute a standard part of the evaluation of candidates for competitive sports. The practice indicates that beyond subjects with severe heart diseases and those classified as normal, there is a group of individuals with abnormalities which should be more closely monitored, but are not contraindications against professional sports or work with an increased energy expenditure. We describe the case of a young female with a diagnosis of rare congenital aortic valve disease, quadricuspid valve, with mild regurgitation and atrial septal aneurysm which was established during transthoracic echocardiography and confirmed and expanded during TEE examination.